68 Vertebrate. 



Among the most remarkable tropical forms are 

 the lyre-birds of Australia, the oven-builders of Brazil ; 

 the sun-birds, nuthatch, wax-wings, &c. 



39. Order 6, Birds of Prey (Raptores). This 

 order consists of eagles, owls and vultures, which 

 feed on animal food, and are armed with strongly 

 hooked bills (fig. 30), and with strong, sharp and 

 curved claws (fig. 29). At the base of the bill is a 



Fig. 29. FIG. 30 



Foot of eagle. Head of eagle. 



cere or skin, which is pierced by the nostrils. The 

 gizzard is weak, the digestive tract short, the sense 

 organs are acute and powerful. Their strong wings 

 have ten primary feathers, and the tail has twelve 

 rectrices. Owls are mostly nocturnal, round-faced 

 birds, with short beaks, and with eyes directed for- 

 wards. They have no crop, and peculiarly soft plu- 

 mage. Some have tufts of feathers above the ears, 

 such as the horned owls. Vultures are carrion-eaters, 

 most abundant in warm climates, with naked or down- 

 clad head and longer bills. Eagles have feather- 

 clad heads, and short, sharply-hooked bills, and they 

 for the most part feed on prey which they kill for 



